The present invention relates to an improvement in a dust collector wherein, by filtration and separation, the collection of powdery dust in general by a dust collector during the disassembly of a mold after pouring in a foundry, the removal of a product, the reclamation of casting sand, etc., or in a dust collector used to separate and collect powdery dust generated by delivery performance, vibration, etc. during various process of casting sand, the powdery dust adhering to the filter members being separated efficiently in order to prevent the lowering of filtering efficiency by the dust adhering to the outside of filter members after long periods of continuous operation.